Brain imaging study shows that lonely individuals “process the world idiosyncratically”

A new study published in Psychological Science investigated the relationship between loneliness, brain activity, and social interactions. The results suggest that individuals who experience loneliness may process social information differently from those who do not, contributing to feelings of isolation and disconnection.

The study highlights the importance of social connection for psychological well-being. It emphasizes the need for further research in this area to develop effective interventions to help individuals experiencing loneliness improve their social connections and overall quality of life.

Humans are social creatures, and social connection is essential for physical and mental health. Social isolation and loneliness have been linked to various adverse outcomes, including depression, anxiety, cardiovascular disease, and even mortality.

Loneliness is defined as the subjective feeling of social isolation or lack of social connection. It is a common experience that can affect individuals of all ages and backgrounds. However, it is particularly prevalent among young adults, with studies suggesting that up to 80% of college students experience feelings of loneliness at some point during their academic careers.

Additionally, feeling understood by others is a critical factor for achieving social connection and is associated with greater life satisfaction. When individuals feel understood by others, they are more likely to engage in prosocial behaviors such as helping and cooperating with others. They are also more likely to experience positive emotions such as happiness and contentment.

In their new study, Elisa Baek and colleagues sought to investigate whether inter-subject correlations (ISCs) in brain activity during a naturalistic movie-watching task are associated with loneliness. ISC measures the similarity in brain activity between two or more individuals. It has been used in previous studies to investigate how individuals process and respond to social information.

The methods involved collecting data from 66 first-year students at a large public university in the United States between 18 and 21 years old. Participants were scanned using functional MRI while watching a movie clip that depicted two people interacting in a socially meaningful way. The task was chosen because it allowed researchers to investigate how the participants’ brains responded to naturalistic social stimuli rather than artificial laboratory tasks.

The results showed that higher levels of loneliness were associated with lower ISC in several brain regions, including the dorsal medial prefrontal cortex, anterior cingulate cortex, and superior temporal sulcus. These regions are known to be involved in social cognition and processing of social information.

The results also revealed that higher levels of loneliness were associated with greater activation in regions associated with negative affect, such as the insula and amygdala, suggesting that loneliness may be associated with increased sensitivity to negative social cues and a heightened perception of social threat.

“Our results suggest that lonely people process the world idiosyncratically, which may contribute to the reduced sense of being understood that often accompanies loneliness,” Baek and colleagues wrote. “In other words, we found that nonlonely individuals were very similar to each other in their neural responses, whereas lonely individuals were remarkably dissimilar to each other and to their nonlonely peers.”

The researchers said that these findings provide evidence for a neural basis for loneliness, suggesting that individuals who experience higher levels of loneliness may have difficulty processing social information and may be more likely to experience negative emotions during social interactions. The study also suggests that interventions aimed at improving social connections may benefit individuals experiencing loneliness.

The research team acknowledged some limitations to their study; firstly, it only included young adults from one university, which limits generalizability to other populations. Secondly, it only measured loneliness at one point, so it is unclear whether changes in ISC over time are related to changes in loneliness. Finally, while this study provides evidence for a neural basis for loneliness, it is unclear whether these neural differences are a cause or consequence of loneliness.

When summarizing their study, the research team wrote, “Our findings suggest that processing the world differently from people around oneself is linked to loneliness. … Therefore, being surrounded by people who view the world differently from oneself may be a risk factor for loneliness, even if one socializes regularly with them.”

The study, “Lonely individuals process the world in idiosyncratic ways,” was authored by Elisa C. Baek, Ryan Hyon, Karina López, Meng Du, Mason A. Porter, and Carolyn Parkinson.

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